Retractable auxiliary supporting devices for wheeled load-handling machines



Nov. 7, 1961 1. NoLY 3,007,717

RETRACTAELE AUXILIARY SUPPORTING DEVICES FOR WHEELED LOAD-HANDLING MACHINES Filed Jan. 25, 1961 f' l 3 N X I 2 1 13 43 1 v l I I l ,l /l\ /I 7]' lll/[life 111111114 'll/Lm ffii/'111111111111111'. 111111111111 la (11u w lllh 105 4a 1e aa'aa 177 6 I 13 l I INVENTOR United States Patent O 3 007 717 RETRACTABLE AUXILIRY SUPPORTING DE- VICES SFOR WHEELED LOAD-HANDLING MA- This invention relates to auxiliary retractable lateral supporting devices adapted :to be mounted on the frame or chassis of wheeled -machines such as cranes and the like, for increasing their operative supporting width with respect to the supporting ground, without impairing the possibilities of travelling on highways, roads and the like.

It is known to provide a movable frame or chassis with a number of laterally extensible arms actuated by appropriate means, as for instance hydraulically. -Each arm has at its outer end a base or shoe adapted to rest on the ground surface when the said arm is at its fully extended position. The said shoe should of course be lowered and raised in unison with the movement of the arm itself.

The present invention has for its object to provide an auxiliary retractable supporting device wherein the actuation of the laterally extensible arm and the actuation of the base or shoe carried by the outer end of the said extensible arm may be ensured in proper succession by a single hydraulic ram or like power means.

In accord-ance with the present invention an auxiliary retractable laterally supporting device comprises an openended substantially horizontal movable arm, guiding means to permit substantially horizontal longitudinal displacement of 4the said movable arm, means to limit the stroke of the said arm between an extended position and a contracted position, -a swingable member hinged to the outer end of the said arm about a substantially horizontal axis transverse to the arm, a shoe pivoted to the said swingable member to be lowered or raised by rotation thereof respectively in one or the other direction, spring means biasing the said swingable member towards a position for which the said shoe is raised, and a ram extending substantially longitudinally through the inner end of the said arm, the said ram acting on the said swingable member to rotate the latter against the action of the said spring means, whereby when the said ram is actuated at the retracted position of the device, it rst moves the arm to the extended position thereof, the swingable member being retained at the raised position of the shoe by the spring means, and thereafter the ram rotates the said swingable member .to bring the shoe to the lowered position.

In the annexed drawings:

FIG. l is a diagrammatical rear view showing a truck or lorry equipped with two devices according to the invention, these devices being shown at the retracted position.

FIG. 2 is a view similar to PIG. l, but the devices being at the extended position.

eFIG. 3 is a large scale longitudinal section of a device at the retracted position.

FIG. 4 is a view similar to FIG. 3, but showing the device at the extended position.

`Referring to EIGS. l and 2 a pair of supporting devices, generally referenced 1, is mounted on the frame or chassis of a wheeled load handling machine, as for instance of a crane carried by a truck or lorry. This frame has not been illustrated but for a better understanding of the present invention its rear wheels 2 have been indicated in dash lines. -Each device has a laterally exten- 3,007,717 Patented Nov. 7, 1961 ICC sible arm 3 the outer end of which carries a ground engaging shoe 13, the arms 3 extending of course respectively on one and the other side of the frame or chassis.

`Each device comprises a transversely disposed tubular member 4 of rectangular or square cross section in which is slidably mounted -a tubular movable arm 3 of corresponding cross-section, the said arm being appropriately `guided yby rollers 3a and by guiding surfaces 4a provided within member 4, as for instance on the inner upper side of the said member and :adjacent the outer end thereof through which arm 3 is adapted to project laterally, arm 3 and member 4 thus forming a telescopic arrangement. This outer end is cut obliquely, `as shown, its upper edge projecting laterally with respect to its lower edge. The opposed end of the tubular member 4 is closed by an end cover 5 `secured in position by any appropriate means, as for instance by welding.

To the end cover 5 of member 4 is hinged, as for instance at 6, Ithe cylinder 7 `of a hydraulic ram which extends into arm 3. This ram has a piston (not illustrated) which is slidably disposed within cylinder 7 and the rod 8 of this piston has at its outer end a bifurcated head or stirrup `8a .which is hinged at 9 to a triangular swingable member or lever '10, the latter `being itself pivoted on a horizontal rod or pin 11 transversely carried by arm 3 in the immediate vicinity of the open outer end thereof. The triangular swingable member 10 further carries a pin 12 on which is articulated a triangular shoe 13 having a flat base 13a. It will be appreciated that member 10 may be considered as a two-armed lever having its arms at approximately lto each other, one arm being articulated -to the movable end of the hydraulic ram, while the other arm carries the shoe 1-3 adapted to rest on the ground by its base 13a.

A forked member 14a is hinged to lever 10 substantially between the above mentioned pins 9 and 11, the said member v14a being secured to one end of a rod 14 disposed within the arm 3. Rod 14 passes through a lug 15 secured to arm 3 and it carries a relatively strong compression spring 16 disposed between two washers 17, one of which bears against lug 15 while the other bears against a nut 14b screwed on the end of rod 14 opposed to member 14a.

The device described operates as follows: The extensible arm 3 is normally at the contracted or ineffective position of FIGS. l and 3. The truck or lorry may thus travel freely on roads or highways without any laterally projecting part. It will be observed that the outer shoe 13-13a is raised and well above ground level. When it is desired to extend the arm and to lower the ou-ter shoe, the hydraulic ram 7-3 is actuated, whereby the hinge pin 9 is pushed outwardly, i.e. towards the left as seen in FIG. 3. Lever 10 being retained against the upper inner side of arm 3 by rod 14 and spring 16, the force developed by ram 7-8 is` transmitted to arm 3 which is therefore displaced outwardly towards the left in F-IG. 3, i.e. extended, until its inner end, which carries the rollers 3a, engages the innermost bearing surface 4a. The outward movement or extension of arm 3 is Ithus stopped, the liquid pressure in the ram increases and the force exerted on lever 10 becomes suicient to overcome the reaction of spring 16. The said lever is therefore rotated anticlockwise as seen in FIGS. 3 and 4, and .the outer shoe 13 is lowered until its base 13a rests on the ground (position of lFlG. 4). The actu-ating ram 7-8 is then at .the end of its outward stroke.

1t will be observed that shoe 13 is only lowered when arm 3 is fully extended and that therefore the extension of the said arm is not liable to be hindered by shoe 13 on account of irregularities of the ground surface.

When the device is to be returned to the ineiective or retracted position of FIG. 3, ram 7-8 is actuated in the reverse direction. This rst permits lever 10 to rotate clockwise under the `action of spring 16 until it abuts against the upper inner side of arm 3. Further movement of the rod 8 of ram 7 8 causes displacement of arm 3 towards the right as seen in FIG. 4, i.e. inwardly. In other words, arm '3 is contracted until ram 7-8 reaches the end of its inward or contracting stroke.

I claim: p

1. A laterally extensible auxiliary retractable supporting device for wheeled load handling machines such as cranes and the like comprising an open-ended substantially horizontal tubular movable arm having an -inner end and an outer end; guiding means to permit substantially horizontal longi-tud-inal `displacement of said arm a-t a vertical distance above ground surface; means to limit displacement of said arm between lan extended position for which said outer end is remote from said guiding means and a contracted position for which said outer end is substantially adjacent said guiding means; a swingable member hinged to the outer end of said `arm about a subst antially horizontial axis transverse to said arm; a shoe pivoted to said swingable member to be lowered onto or raised from ground surface by rotation of said member respectively in one or the other direction;v means to limi-t angular displacement of said swingable member between a tirs-t position for which said shoe fully engages ground surface and a second position `for which 'said shoe is raised at a predetermined height above ground surface; spring means biasing said swingable member towards said second position; and a ram extending substantially longitudinally through the inner end of said arm, said ram acting on said member to rotate same against the action of said spring means when said arm is at the contracted position and when said member is at Said second position, so as to first move said arm to the extended position and thereafter bring said member to said first position.

2. In an auxiliary retractable supporting device as claimed in claim 1, said guiding means comprising a substantially horizontal outer tube substantially forming a telescopic unit with said movable arm.

3. In an auxiliary retractable supporting device as claimed in claim 1, said guiding means comprising a substantially horizontal outer tube substantially forming ya telescopic unit with said movable arm, said outer tube having a closed end and an open end through which said movable arm protrudes, and said ram being hinged to the closed end of said outer tube.

4. In an auxiliary retractable device as claimed in claim 1, said swingable member being in the form of a substantially triangular lever having a first apex lhinged to said arm, a second apex hinged to said shoe, and a third apex hinged to said ram.

References Cited in the le of this patent UNITED STATES PATENTS a fr c., y... 

